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    <span class="topic">Namco 163</span>
    <hr />
    
    <p class="heading">About</p>
    
    <p class="text">
        This chip was created by Namco and contains up to eight wave channels, this chip 
        was earlier erroneously known as Namco 106 (which is the same chip but without 
        the audio capabilities). It was used in multiple Namco games, such as 
        Final Lap, King of Kings and Rolling Thunder.</p>
    
    <p class="text">
        The chip has 128 bytes of RAM for wave storage, but the last 64 bytes is shared 
        with the audio registers so the wave area is practically limited to 64 bytes (or 
        128 wave steps). Each channel can use a wave size from 4 to 256 steps, but most 
        NSF players supports only 32 steps as the largest size. This is also the limitation 
        in the tracker at the moment.</p>
        
    <table class="noteFrame" cellpadding="5px"><tr><td>
        <p class="text">
            <b>Note:</b> This chip has 8 channels in total, but the actual number of channels to use 
            is configurable (from the module properties dialog). This is of importance 
            because all channels are clocked sequentally by the chip, so the pitch range 
            will depend on the channel count: a lower number of channels allows an extended 
            top pitch range. More channels will also increase the effects of aliasing (since 
            this chip uses phase accumulation for tone generation).</p>
            
        <p class="text">
            What is even more important is that the DAC is also shared by 
            all channels in the same sequential manner. The rate for this channel switching 
            is 120 kHz, which means that <b>when all 8 channels are enabled, there will be 
            audible channel switching noise at 15 kHz</b> (or 17 kHz when 7 channels are 
            enabled). The Namco cart did not have a LP filter to deal with this, so it 
            is very audible. To avoid this, do not use 8 (or 7) channels. Most games used 
            only four channels. This behaviour is not commonly emulated by NSF players 
            (at the moment), with the exception of NEZplug++.</p>
    </td></tr></table>
    
    <hr />
    <p class="heading">Instruments</p>
    
    <p>
        <IMG id="IMG1" style="FONT-SIZE: 10pt" src="img/inst_n163.PNG" alt="Namco instrument editor"></p>
    
    <p class="text"><b>Envelopes</b></p>
    
    <p class="text">
        Namco instruments has an envelope editor that behaves like 2A03, with the 
        exception for an extra wave setting.</p>
        
    <p class="text">
        See <a href="2a03.htm#Instruments">2A03 instruments</a> for more information.</p>

    <p class="text"><b>Wave</b></p>
    
    <p class="text">
        This tab is used to define waves for the instrument, the wave editor is the same 
        as used for FDS except that only 16 levels are available and the wave size is 
        customizable. Like for FDS, a few presets are available.</p>
    
    <p class="text">
        Up to 16 different waves can be stored in the same instrument, and the wave to 
        actually use is controlled by the wave envelope setting or the V pattern effect. 
        Only one wave is uploaded the the wave memory at the time.</p>
    
    <p class="text">
        The location in the wave memory is customizable, and the user is responsible for 
        being sure that no instruments tries to use the same memory position 
        simultaneously! For example, two instruments that uses wave position 0 cannot be 
        used at the same time, but can be used at different times. Two instruments that 
        uses wave position 0 and 32 can be used simultaneously.</p>
    
    <p class="text">
        The instrument editor will suggest wave positions depending on the wave size.</p>
    
    <p class="text">
        Also be aware that the pitch table is calculated with 32 steps waves in mind, so 
        waves that are not a power of two in size will be out of tune.</p>

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